Twice during the current game I agreed to put embargo. This "embargo" agreement shown in the correspondent race status... but I see no place to lift it! I found even one place to demand others to lift embargo, but I have no idea how to remove my own. How can I do that?

(Also I wonder how to check race relations between each other. It seems, I am too dumb to notice it.

Another similar treaty is the "Peace" one. It looks permanent to me, and cannot be canceled. Am I right?